The invention is directed to a press fitting for a pipe, in particular for a plastic pipe or a pipe of a plastic/metal composite material.
Press fittings for the connection of pipes are known in a number of designs. They mostly comprise a compression sleeve that radially deformed by means of a pressing tool, whereby the connection end of the pipe surrounded by the compression sleeve is pressed against a supporting body of the fitting and is sealed thereby.
To facilitate the mounting of a press fitting of the type mentioned above, manufacturers are known to permanently connect the compression sleeve with the fitting body. Thereby, a an annular space open to one side is formed between the compression sleeve and the supporting body of the fitting body, into which space the pie end to be connected is pushed. Examples for press fittings comprising a compression sleeve connected with the fitting body are described in DE-A-42 31 623 and DE-C-100 10 573.
Besides a direct connection of the press fitting and the fitting body, it is also known in prior art to connect these two elements of a press fitting through an annular connection member. Examples of such press fittings are found in DE-C-43 04 680, EP-A-0 611 911, DE-U-295 03 019, DE-A-198 45 720 and EP-A-0 942 219. Some of the annular connection elements known from these publications have the additional purpose of providing for a galvanic separation of the front end of the pipe and the fitting body, as well as for a guiding of the pressing tool. The latter purpose is also fulfilled by the plastic rings described in DE-A-100 21 988 and DE-U-299 07 585, which surround the compression sleeves of these known press fittings on the outside.
Finally, it also known to provide the compression sleeves of press fittings with position control openings. These openings allow the fitter to check right before pressing, whether the pipe end to be connected is correctly slipped onto the supporting body of the press fitting. Examples of press fittings with position control openings are described in the two above-mentioned publications, i.e. DE-C-100 10 573 and DE-U-295 03 019, as well as in DE-C-198 45 720, DE-A-197 41 641, DE-A-196 03 228, DE-A-195 45 361 and DE-U-297 11 313.
From DE-B-102 33 559, a press fitting comprising a compression sleeve held at a supporting body, which is slit at the holding end held at the supporting body, the holding end being surrounded by an axially fixed plastic ring.
Further, it is desirable for the press fitting to visually indicate that a pressing be means of the pressing tool has been performed (pressing indication). Such a press fitting is described in DE-U-299 07 585 and comprises a plastic ring serving as a guiding ring for the pressing tool and being made of a material destructible under the effect of the pressing tool.